Some robots and/or robot control systems construct and/or maintain a three-dimensional (“3D”) model of at least portions of an environment in which the robot operates. For example, a robot may acquire data from a 3D vision component (e.g., a 3D laser scanner or a stereographic camera) viewing a portion of the robot's environment, and map such data to the 3D model. Some 3D models are formed as so-called “voxel-based” 3D models (“3D voxel models”), in which a 3D matrix of voxels are allocated. For example, data points generated by one or more 3D vision components (also referred to as a “3D point cloud”) can be projected onto spatially-corresponding voxels of the 3D voxel model.
Further, some robots and/or robot control systems utilize 3D models for various robotics applications, such as path planning. For example, one or more path planning algorithms can utilize a “current” 3D model in generating a path of the robot from a “current position” of the robot to a “target position” of the robot. For instance, the path planning algorithm(s) can be utilized to generate a collision-free path while considering occupied voxels, of a 3D voxel model, as obstacles to be avoided—and while considering unoccupied voxels, of the 3D voxel model, as points through which the collision-free path may pass. In generating a path, all voxels of a 3D voxel model are typically considered to have the same volume. For example, each of the occupied voxels of the 3D voxel model can be transformed into a corresponding cube of a particular volume, and those particular volume cubes considered as obstacles in generating the path.